A new multifunctional sensor for sequential recognizing of Zn2+ and PPi in acetonitrile solution and detection of In3+ in DMF solution

Abstract A simple multifunctional sensor, X, was designed and synthesized based on 8-hydroxy-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinoline-9-carbaldehyde and imidazo[2,1-b]thiazole, which could sequentially identify Zn2+ and PPi in acetonitrile buffer solution through the presence or absence of fluorescent signals and could detect In3+ in DMF buffer solution with obvious fluorescence enhancement. The detection limit for Zn2+, PPi and In3+ were calculated to be 4.58 × 10-8 M, 1.07 × 10-8 M and 2.9 × 10-8 M, respectively. Moreover, X could quantitatively detect Zn2+, PPi and In3+ in real water samples with the satisfactory recovery rate (90.1% - 97.6%) and RSD (0.86% - 3.09%). In addition, the complexation ratio between X and metal ions (Zn2+ and In3+) was 1:1, which was proved by mass spectrometry titration. The binding mode and sensing mechanism of X to metal ions (Zn2+ and In3+) were verified by Gaussian calculation based on B3LYP/6-31 G(d) and B3LYP/LanL2DZ basis set.